Found this a few nights back! Not sure if its a repost or what but thought that you might be interested! It is basically a program that shows you what difference changing sprocket sizes on the bike will do to it performance-wise and speed-wise! Took me a while to figure out what I was doing (not the brightest when it comes to mechanics )...... Check the bike model up the top and DT is in there! I'm sure some of you will find good use for it!!